/*
 * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/methods/multipart/FilePart.java,v 1.19 2004/04/18 23:51:37 jsdever Exp $
 * $Revision: 480424 $
 * $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $
 *
 * ====================================================================
 *
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.commons.httpclient.methods.multipart;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.httpclient.util.EncodingUtil;
import org.apache.commons.logging.Log;

/**
 * This class implements a part of a Multipart post object that consists of a
 * file.
 * 
 * @author <a href="mailto:mattalbright@yahoo.com">Matthew Albright</a>
 * @author <a href="mailto:jsdever@apache.org">Jeff Dever</a>
 * @author <a href="mailto:adrian@ephox.com">Adrian Sutton</a>
 * @author <a href="mailto:becke@u.washington.edu">Michael Becke</a>
 * @author <a href="mailto:mdiggory@latte.harvard.edu">Mark Diggory</a>
 * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
 * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
 * 
 * @since 2.0
 * 
 */
public class FilePart extends PartBase {

	/** Default content encoding of file attachments. */
	public static final String DEFAULT_CONTENT_TYPE = "application/octet-stream";

	/** Default charset of file attachments. */
	public static final String DEFAULT_CHARSET = "ISO-8859-1";

	/** Default transfer encoding of file attachments. */
	public static final String DEFAULT_TRANSFER_ENCODING = "binary";

	/** Log object for this class. */
	// private static final Log LOG = LogFactory.getLog(FilePart.class);

	/** Attachment's file name */
	protected static final String FILE_NAME = "; filename=";

	/** Attachment's file name as a byte array */
	private static final byte[] FILE_NAME_BYTES = EncodingUtil
			.getAsciiBytes(FILE_NAME);

	/** Source of the file part. */
	private PartSource source;

	/**
	 * FilePart Constructor.
	 * 
	 * @param name
	 *            the name for this part
	 * @param partSource
	 *            the source for this part
	 * @param contentType
	 *            the content type for this part, if <code>null</code> the
	 *            {@link #DEFAULT_CONTENT_TYPE default} is used
	 * @param charset
	 *            the charset encoding for this part, if <code>null</code> the
	 *            {@link #DEFAULT_CHARSET default} is used
	 */
	public FilePart(String name, PartSource partSource, String contentType,
			String charset) {

		super(name, contentType == null ? DEFAULT_CONTENT_TYPE : contentType,
				charset == null ? "ISO-8859-1" : charset,
				DEFAULT_TRANSFER_ENCODING);

		if (partSource == null) {
			throw new IllegalArgumentException("Source may not be null");
		}
		this.source = partSource;
	}

	/**
	 * FilePart Constructor.
	 * 
	 * @param name
	 *            the name for this part
	 * @param partSource
	 *            the source for this part
	 */
	public FilePart(String name, PartSource partSource) {
		this(name, partSource, null, null);
	}

	/**
	 * FilePart Constructor.
	 * 
	 * @param name
	 *            the name of the file part
	 * @param file
	 *            the file to post
	 * 
	 * @throws FileNotFoundException
	 *             if the <i>file</i> is not a normal file or if it is not
	 *             readable.
	 */
	public FilePart(String name, File file) throws FileNotFoundException {
		this(name, new FilePartSource(file), null, null);
	}

	/**
	 * FilePart Constructor.
	 * 
	 * @param name
	 *            the name of the file part
	 * @param file
	 *            the file to post
	 * @param contentType
	 *            the content type for this part, if <code>null</code> the
	 *            {@link #DEFAULT_CONTENT_TYPE default} is used
	 * @param charset
	 *            the charset encoding for this part, if <code>null</code> the
	 *            {@link #DEFAULT_CHARSET default} is used
	 * 
	 * @throws FileNotFoundException
	 *             if the <i>file</i> is not a normal file or if it is not
	 *             readable.
	 */
	public FilePart(String name, File file, String contentType, String charset)
			throws FileNotFoundException {
		this(name, new FilePartSource(file), contentType, charset);
	}

	/**
	 * FilePart Constructor.
	 * 
	 * @param name
	 *            the name of the file part
	 * @param fileName
	 *            the file name
	 * @param file
	 *            the file to post
	 * 
	 * @throws FileNotFoundException
	 *             if the <i>file</i> is not a normal file or if it is not
	 *             readable.
	 */
	public FilePart(String name, String fileName, File file)
			throws FileNotFoundException {
		this(name, new FilePartSource(fileName, file), null, null);
	}

	/**
	 * FilePart Constructor.
	 * 
	 * @param name
	 *            the name of the file part
	 * @param fileName
	 *            the file name
	 * @param file
	 *            the file to post
	 * @param contentType
	 *            the content type for this part, if <code>null</code> the
	 *            {@link #DEFAULT_CONTENT_TYPE default} is used
	 * @param charset
	 *            the charset encoding for this part, if <code>null</code> the
	 *            {@link #DEFAULT_CHARSET default} is used
	 * 
	 * @throws FileNotFoundException
	 *             if the <i>file</i> is not a normal file or if it is not
	 *             readable.
	 */
	public FilePart(String name, String fileName, File file,
			String contentType, String charset) throws FileNotFoundException {
		this(name, new FilePartSource(fileName, file), contentType, charset);
	}

	/**
	 * Write the disposition header to the output stream
	 * 
	 * @param out
	 *            The output stream
	 * @throws IOException
	 *             If an IO problem occurs
	 * @see Part#sendDispositionHeader(OutputStream)
	 */
	protected void sendDispositionHeader(OutputStream out) throws IOException {
		// LOG.trace("enter sendDispositionHeader(OutputStream out)");
		super.sendDispositionHeader(out);
		String filename = this.source.getFileName();
		if (filename != null) {
			out.write(FILE_NAME_BYTES);
			out.write(QUOTE_BYTES);
			out.write(EncodingUtil.getAsciiBytes(filename));
			out.write(QUOTE_BYTES);
		}
	}

	/**
	 * Write the data in "source" to the specified stream.
	 * 
	 * @param out
	 *            The output stream.
	 * @throws IOException
	 *             if an IO problem occurs.
	 * @see org.apache.commons.httpclient.methods.multipart.Part#sendData(OutputStream)
	 */
	protected void sendData(OutputStream out) throws IOException {
		// LOG.trace("enter sendData(OutputStream out)");
		if (lengthOfData() == 0) {

			// this file contains no data, so there is nothing to send.
			// we don't want to create a zero length buffer as this will
			// cause an infinite loop when reading.
			// LOG.debug("No data to send.");
			return;
		}

		byte[] tmp = new byte[4096];
		InputStream instream = source.createInputStream();
		try {
			int len;
			while ((len = instream.read(tmp)) >= 0) {
				out.write(tmp, 0, len);
			}
		} finally {
			// we're done with the stream, close it
			instream.close();
		}
	}

	/**
	 * Returns the source of the file part.
	 * 
	 * @return The source.
	 */
	protected PartSource getSource() {
		// LOG.trace("enter getSource()");
		return this.source;
	}

	/**
	 * Return the length of the data.
	 * 
	 * @return The length.
	 * @throws IOException
	 *             if an IO problem occurs
	 * @see org.apache.commons.httpclient.methods.multipart.Part#lengthOfData()
	 */
	protected long lengthOfData() throws IOException {
		// LOG.trace("enter lengthOfData()");
		return source.getLength();
	}

}
